1. Field of the Invention
The present invention relates to a friction heater which includes a male rotor which is inserted into a female stator. Rotation of the rotor produces friction which heats the rotor and stator as well as an enclosed reservoir housing which extends around the periphery of the stator such that liquid contained within the housing is heated.
2. Description of Prior Art
It is well known in the art to use friction to produce heat to heat a liquid. For example, U.S. Pat. No. 4,554,906 to Newman, Sr. et al. relates to a system which includes a cylindrical rotary member which has an outer surface which engages a complimentary surface of a liner into which the rotary member extends. The friction caused by the rotation of the rotary member relative to the surface of the liner generates heat in the liner which in turn heats liquid contained in tanks disposed adjacent the liner. Adjustment means are provided to adjust the contact between the rotary member and the liner.
Another known prior art patent is U.S. Pat. No. 4,721,066 to Newman, Sr. et al. which describes a friction heater which includes a rotating drum housing in the shape of a truncate cone having an external surface which engages a bore surface of a housing, such bore surface having the same conical dimension as the external surface of the truncate cone. An external surface of the housing includes a helical groove coaxially around it, and wound around the helical groove is copper tubing. The friction caused by the rotation of the rotary drum relative to the bore surface generates heat in the housing which in turn heats liquid flowing through the copper tubing. In such apparatus it is difficult to maintain intimate contact between the copper tubing and the surface of the helical groove and consequently there tends to be heat loss at the interface between the tubing and the groove. In addition, the quantity of the liquid flowing through the tubing is not very great due to the limited volume of the tubing.
It is an object of the present invention to provide an improved friction heater.
It is a further object of the present invention to provide a friction heater wherein heat is more efficiently transferred from a stationary stator to an adjacent wall of an enclosed reservoir housing which contains a liquid to be heated without loss of heat at the interface between the stator and the wall.
It is yet another object of the present invention to provide a friction heater wherein means is provided to increase the dwell time of a liquid flowing through an enclosed reservoir housing wherein the liquid is being heated.